The invention relates generally to vehicular fuel systems having carburetors and particularly to a fuel injection adapter therefor.
While the invention will be described in conjunction with automobiles and automobile carburetors, it will be appreciated that the invention is not restricted to automobiles but may be used on any type vehicular apparatus using gasoline as fuel and having a carburetor. As is well known, carburetors control the mixing of gasoline vapor and air in the proportions required for proper combustion efficiency. To that end, most carburetors include a plurality of fuel jets or orifices that communicate by means of tubes or passages with a fuel supply and that are exposed to flow of air in a Venturi tube formed in the throat of the carburetor. The flow of air causes siphoning and vaporization of the gasoline from the exposed jet openings. Air flow is controlled by opening a throttle valve plate located in the carburetor throat. This may be accompanied by movement of a needle in a metering jet that enlarges the fuel passage and enables a larger quantity of fuel to be siphoned. For cold weather starting, a richer fuel-air mixture is required and a separate choke valve plate is generally used to restrict the flow of air. The choke valve may be thermostatically controlled and should reach its fully open position, that is, be non-restrictive to air flow, when the engine operating temperature increases to a point where fuel is readily vaporized.
Needless to say, carburetor mechanisms are complicated, often difficult to adjust, even with elaborate equipment, and are prone to malfunctioning. For example, the carburetor includes a float assembly for automatically closing the fuel inlet to fuel delivery from the automobile fuel pump when the fuel reaches a predetermined level in a float bowl in the carburetor body. Deviations in the fuel level in the float bowl can create significant problems in operation due to the positions of the different fuel orifices in the carburetor throat that are exposed to the air flow by changes in the throttle valve. A proper fuel level in the carburetor float bowl can nullify operation of some of these orifices.
The modern carburetor is also very difficult to "trouble shoot" without the aid of expensive and often cumbersome diagnostic equipment. Consequently, difficulties with a carburetor are generally resolved by replacing or rebuilding the carburetor, both of which can be costly alternatives. Even then, much time may be lost in attempting to locate a problem in the carburetor system.